1. Field of the Invention
The device of this invention resides in the area of portable water purifiers and more particularly relates to a small self-contained easily carried water-filtering device suitable for use in the field with a replaceable filter element.
2. History of the Prior Art
Individuals, when away from drinkable water supplies, need to purify water such as found in lakes, rivers and streams before drinking it. Early purification methods required the boiling of the water and/or the addition of chemicals before it was fit for consumption. These procedures usually did not adequately purify the water and/or imparted to it a foul taste. Therefore water filtration systems were developed to remove contaminants. These water filtration systems pass unpurified water through a filter to trap any contaminants therein. In the past many filtering mediums have been utilized such as felt or cloth as disclosed in the U.S. Pat. No. 53,606 to Gruber patented in 1866. The art has developed considerably over the years and filters utilizing spun or wrapped fibers in a cylinder shape having water passed radially through the cylinder from the outside to its hollow inside have been developed such as seen in U.S. Pat. No. 4,277,333 to Coppola. Other filtering mechanisms deserve mention such as the use of pleated cylindrically-formed filter paper and combinations utilized therewith along with spun fiber and activated carbon. Activated carbon is an excellent element to use in water filters due to its large surface area and its property of removing large dispersed particles making the filtered water very clear. Plastic mesh has been used as a filter medium and is successful in removing particles as small as 1 micron in size. Osmotic membranes which employ a difference in potential to pass, for example, water containing salt ions therethrough while retaining the ions on the unfiltered side of the membrane and the filtered water being ion free have been utilized to remove salt from sea water but this method usually requires very high pressures and further treatments to the water after filtering.
Small portable water filters have been designed for use by backpackers and the like as mentioned above but it has long been desirable to have an exceedingly small, simple, highly portable water purifier such as disclosed herein.